Malacoplakia and rosai‐dorfman disease: Two entities of histiocytic origin infrequently localized in the female breast—the cytologic aspect in aspirates obtained via fine‐needle aspiration cytology

Publisher Website
Google Scholar
Abstract
We describe one case of Rosai‐Dorfman disease (RDD) localized in the breast and one case of breast malacoplakia (MPK) both diagnosed by fine‐needle aspiration cytology (FNAC). In RDD the cytologic features were lymphocytophagocytosis, large histiocytes with slight nuclear atypia, and lymphohistiocytic aggregates in a polymorphous background which included frequent plasma cells. In MPK the key diagnostic feature was the presence of Michaelis‐Gutmann bodies (M‐G bodies), in various stages of evolution, intermingled with vacuolized medium‐sized histiocytes, other inflammatory cells, and debris. Pap staining is the technique of choice to show lymphocytophagocytosis and M‐G bodies and there is no need to resort to special staining methods.RDD and MPK share a common cytologic background: the presence of numerous benign reactive histiocytes, either engulfing apparently intact lymphocytes, or phagocytizing M‐G bodies. The cytologic findings seen in both cases suggest that the presence of histiocytes in a breast aspirate is far from being nonspecific and can represent an important lead to disparate diseases such as RDD and MPK.